Outboard motor manipulating mechanism



June 19, 1962 R. A. HERREMAN 3,

OUTBOARD MOTOR MANIPULATING MECHANISM Filed April 29. 1960 4Sheets-$heet 1 INVENTOR.

ROBERT A. HERREMAN BYWd AT TORNEX FIG.

June 19, 1962 R. A. HERREMAN 3,03 ,724

OUTBOARD MOTOR MANIPULATING MECHANISM FIG.3

INVENTOR.

ROBERT A. HERREMAN ATTORNEY June 1-9, 1962 R. A. HERREMAN 3,039,724

OUTBOARD MOTOR MANIPULATING MECHANISM Filed April 29. 1960 4Sheets-Sheet 3 INV EN TOR.

ROBERT A. HERREMAN BY ATTORNEY June 19, 1962 R. A. HERREMAN 4 OUTBOARDMOTOR MANIPULATING MECHANISM Filed April 29. 1960 4 Sheets-Sheet 4 t HWII/I; H a b /44 F I G. 6

INV EN TOR.

ROBERT A. HERREMAN FIG. 8 7

ATTORNEY United States Patent 3,039,724 OUTBOARD MOTOR MANIPULATINGMECHANISM Robert A. Herreman, 1402 Chester St., South Bend, Ind. FiledApr. 29, 1960, Ser. No. 25,780 11 Claims. (Cl. 248-4) The presentinvention relates to a positioning mechanism for boat motors and moreparticularly to 'a mechanism for lowering and raising outboard motors toand from operating position.

In the past few years outboard motors have been increased in size,weight and horsepower to the extent that they have become extremelydiflicult to raise from their normal operating position to a lockedposition above the water level and also diflicult to lower to operatingposition without permitting the motor literally to fall from its normallocked position above the water. Even for people capable of lifting andlowering the motor, these operations constitute a considerable hazard inthat the operator is required to stand in the boat and/ or lean over thetransom of the boat in order to have a secure grip on the motor for thelifting and lowering operations. Walking to and from the motor is alsooften required in that the boats on which these large motors are usedare normally piloted from a place toward the forward end of the boat,thus presenting an additional hazard for the operator of the boats withthe large motors. Various types of motor lifting and lowering deviceshave been tried, including manual, hydraulic and electrical mechanisms,but these prior devices have either been expensive to build and install,dificult in themselves to operate to raise and lower the motor, or arenot safe to the average non-professional and often inexperienced boatoperator. It is therefore one of the principal objects of the presentinvention to provide an apparatus for raising and lowering outboardmotors, which can be operated by a simple, easily actuated controldevice located at a point in the boat remote from the motor and whichdoes not interfere with the normal operation and control of the motorwhile the motor is in its lowered position.

Another object of the invention is to provide an outboard motor liftingand lowering apparatus which can be operated with no appreciablephysical force or movement on the part of the operator and which can beeffectively controlled by the operator in a sitting or confined positionwithin the boat.

Another object of the invention is to provide an outboard motor liftingand lowering apparatus, which is simple in construction and operationand which can be readily installed on any conventional outboard withoutcutting, drilling or otherwise changing the construction of the boattransom other than securing parts of the apparatus to the boat usingonly a few relatively small screws or bolts.

Still another object of the invent on is to provide an outboard motorlifting and lowering apparatus which locks the motor in its raisedposition automatically as the motor is controlled at a point in the boatremote from the motor, and which automatically releases the motor at thewill of the operator and gently lowers the motor to its normal operatingposition.

A further object is to provide a mechanism of the aforesaid type whichcan be temporarily installed on a boat and easily removed therefromalong with the outboard motor, and which does not occupy any otherwisenormally usable space in the boat.

Another object of the invention is to provide a motor manipulatingmechanism for tiling outboard motors between their operating andnonoperating positions, which applies a balanced thrust against thelower portion of the motor to raise the motor from the water, and whichPatented June 19, 1952 retracts away from the motor when the presentmechanism is not in use.

Additional objects and advantages will become apparent from thefollowing description and accompanying drawings, wherein:

FIGURE 1 is a side elevational view of a boat having mounted thereon anoutboard motor and my motor lifting and lowering mechanism;

FIGURE 2 is an enlarged partial top plan and cross sectional view of theboat, motor and my mechanism shown in FIGURE 1, the section being takenon line 2-2 of FIGURE 1;

FIGURE 3 is an enlarged fragmentary and partial cross sectional View ofmy motor lifting and lowering mechanism, showing it mounted on thetransom of the boat;

FIGURE 4 is a side elevational view of an outboard motor and my liftingand lowering mechanism mounted in running position on the transom of aboat;

FIGURE 5 is a side elevational view of the outboard motor and thelifting and lowering mechanism with the motor being held in its liftedposition by the mechanism;

FIGURE 6 is a vertical cross sectional view of the control unit for thepresent motor lifting and lowering mechanism;

FIGURE 7 is a fragmentary vertical cross sectional view of a lockingmechanism for holding the motor in its lifted position, the sectionbeing taken on line 77 of FIGURE 2; and

FIGURE 8 is a horizontal cross sectional view of the locking mechanism,taken on line 8-8 of FEGURE 7.

Referring more specifically to the embodiment of my inventionillustrated in the drawings, numeral 10 designates an outboard motorboat having a transom 12 on which an outboard motor 14 is shown mountedin its lowered position in F iGURES l and 2 for propelling the boat, andin its raised position out of the Water in FIGURE 5. The boat is adaptedto be piloted from a seat 16 located forward in the boat, by a steeringwheel 13 mounted on a steering mechanism connected to motor 14 bysuitable cables and pulleys (not shown) attached to the boat structure.One or more additional seats may be provided in the boat to the rear ofseat 16, including one at the rear of the boat adjacent transom 12,without interfering with the installation of my mechanism. For thepurpose of the present description both the boat and outboard motor maybe considered as conventional and the present invention is not limitedin its application to any particular kind or make of outboard motor, theone shown being, for example, a forty horsepower unit consisting of amotor enclosed in a housing 29 and connected to a propeller 22 by adrive shaft disposed in a leg 24 rigidly connected at its upper end tothe motor frame or supporting housing 20 and terminating at its lowerend in a rudder 25. The outboard motor, which term hereinafter refers tothe entire unit unless otherwise specified, is mounted on the boattransom 1.2 by a mounting device 26 including a swivel bracket 28secured to the motor and a stern bracket 30 pivotally connected tobracket 28. The swivel bracket 28 holds the motor so that it can beoscillated on an upright axis for steering. The stern bracket 3%} isadapted to seat over the top of transom 12 and to be secured thereto bya plurality of clamping units 32 consisting of a shaft 34 threadedlyreceived in a portion of bracket 36] and a bandle 36 for rotating theclamp. The pivoting of the swivel bracket relative to the stern bracketpermits the motor to be tilted downwardly into operating position asshown in FIGURES l and 4. In conventional mountings of this general typea thrust receiving member 1 adjustable to various positions receives theforward thrust from the swivel bracket and transmits the propellingforce of the motor to the boat.

Most of the more expensive models of outboard motors are equipped with alatching mechanism for locking the motor in its upright operatingposition so that the operation of the motor can be reversed without themotor tilting upwardly from the water. While the mechanism for lockingthe motor in its operating position may be considered conventional andis therefore not disclosed in detail herein, a lever for manuallyoperating the latching mechanism is shown at numeral 44, said leverbeing moved downwardly to release the latch mechanism to permit themotor to be tilted from the water.

The embodiment of my outboard motor raising and lowering mechanism shownin the drawings consists of a power lifting unit 59 and power controland supply units 52 and 54, respectively, unit including cylinders 56and 58 projecting rearwardly from the transom of the boat on oppositesides of the outboard motor positioned approximately half waydown leg24. The cylinders are rigidly connected to one another by a U-shapedsaddle 60 of which arm 62. is secured to cylinder 56 by bolts 64 and 66and arm 63 to cy inder 58 by bolts 73 and 72.. The two arms areconnected by a cross member 74 which is adapted to contact the adjacentside of leg 24 when the lifting unit is operated. The cylinders aresubstantially the same and are closed by end caps 75 and 76 and cylinder56 contains a piston 78 and rod 8i; connected to the rear of the transomby a bracket 82, and cylinder 53 contains a piston se and rod 86connected to the transom by a bracket 37. The two brackets are securedto the rear side of the transom by suitable screws extending into thetransom and are pivotally connected to rods 8% and 36 by pins 88 and alrespectively. Each rod contains a longitudinal passage 92. extendingfrom the piston end through most of its length and connects the outerend of the cylinder with atube 94, which in turn is connected by a tube96 to control unit 52 and thence by a tube 98 to power supply unit 54.In order to prevent a sudden sunge of power into the cylinders when thecylinders are actuated by a supply of compressed gas, restrictions 1%and 1&2 are preferably included in tube 94 adjacent rods 3% and 8d and astill further restriction 3.04 in tube 96. Pistons 7'8 and 34 may be ofany well known conventional design, the type shown in the drawingsconsisting of a washer 196 seated against a shoulder 16% on the pistonrod, and a cup shaped gasket Tilt? clamped against the Washer by asecond washer 112 nut 114 threaded on to the end of the rod. in order toprevent excess pressure from being built up the two cylinders by gassupplie from the source 54, a vent hole 116 is placed in the side wallof each cylinder at the end of the power stroke to relieve the pressureand to form an effective stop for limiting the travel of the piston inthe cylinder. As used in the specification and claims, the term rear endof the piston 'efers to the right hand end as seen in the drawings.

The saddle oil is held in the desired position on the motor leg 24 bysupport rods 11% and 1 pivotally connected to cylinders as and 53,respectively, and pivotally connected to the transom near the topthereof by suitable brackets. These two rods, one of which may bedispensed with if desired, cause the saddle to pivot upwardly and followthe tilting motor as the pistons are extended during the power stroke,as illustrated in EG- URE 5. Rods 118 and fill also hold the saddle in ahorizontal inoperative position after the motor has been lowered torunning position in the water.

The two cylinders are operated by compressed gas, for example carbondioxide, from a steel cylinder 13d of power supply unit 54. Cylinders 1are available as filled exchangeable units, or they can be readilyfilled with compressed carbon dioxide, air or other suitable gas atreadily available stations. Cylinder 130 is held in place in the boat byany suitable clamping means 132 and is connected to control unit 52 by arubber or copper tube 98, the flow of gas from the cylinder beingcontrolled by a shut-off valve 136 which is mounted on the cylinder andis removed from tube @3 when the cylinder is removed for refilling orreplacement by a full cylinder.

Control unit 52 consists of a valve body 149 having an inlet passage 142connected to tube 98, an outlet passage 144 connected to tube 95, and apassage 146 connecting asid inlet and outlet passages and containing avalve res consisting of a reciprocable valve element 15% with anenlarged end 152 for seating on valve seat 154, and a stem 156 actuatedby a lever 153 pivoted at one side of the stem and engaging the upperend of the stem. The valve element is urged to its seat by a spring 1559around stem 15s and by pressure from cylinder 13%, and is readily openedby the operator by pressing downwardly on the free end 169 or lever 158.The outlet passage is connected to the atmosphere by an exhaust valveled consisting of a valve element 366 urged to its seat 163 by thepressure in the outlet passage and by a spring 17% around stem 172 ofthe valve. The valve is operated when cylinders 56 and 5?: are to beexhausted, by pressing on a button 174 on the outer end of stem 172. Thecontrol unit 56 may be connected directly to the outlet conduit ofcylinder 13%, thus eliminating tube 98. A mechanism 18% forautomatically locking cylinders 56 and S8 in their extended position andthe motor in its raised position, is shown in FlGURES 7 and 8. Mechanism1% consists of a housing 182 secured to the inner end of cylinder 56 andhaving a cylindrical chamber 184 in which is mounted a plunger 186. Theplunger projects from the housing into a recess 138 in rod 3d and formsa stop for the laterally extending shoulder 1% of recess 15% to hold therod in its extended position. The plunger is removed from the slot byagain energizing the piston to move the rod further to the right, asshown in FIGURE 7, and thereby forces the inclined surface 191 againstthe plunger causing the plunger to retract into housing 182. In order tohold the plunger in its retracted position, a sleeve 192 in which theplunger reciprocates is provided with a pair of deep op osed slots 1%and a pair of shallow opposed slots 1% in the inner edge thereof, andthe inner end of the plunger is provided with a transverse pin 193 forseating in corresponding slots. The plunger is rotated a partialrevolution each time it is retracted by engaging a pair of annulartoothed members 2% and 202 on the inner end of plungerlSd and a sleeve264 secured to the end of housing 182 in axial alignment with theplunger. The pitch of the teeth on the members 2% and 2% is such thatplunger 1% is rotated sufliciently to shift pin 19% alternately from thedeep slots to the shallow slots. The longitudinal movement of plunger136 for engaging and rotating the plunger is obtained by a lug 2%secured to rod 89 and having an inclined surface continuing outwardlyfrom inclined surface 191. When the pin is in deep slots 194 the plungerextends into recess 138 and locks rod 86 in its extended position, andwhen the pin is in the shmlow slots 196 the plunger is held in itsretracted position free of rod 8%. A longitudinal groove 21% is providedin the end cap to permit lug 2th, to move into the outer end of the cap.Only one locking mechanism 18% is preferably used since one mechanismperforms the function of holding both rods 8% and 86 extended and avoidsthe need of synchronizing the two mechanisms.

In the operation of the present outboard motor lifting and loweringmechanism, when it is desired to lift the motor from its runningposition shown in FIGURE 4, lever 158 is pressed downwardly by theoperator, opening valve element 148 and admitting compressed gas fromcylinder 136 and tube 98, through tubes and ?4, and passage 92 of rods89 and into the rear end of cylinders 56 and 58. The pressure of the gasin the cylinders forces the cylinders and saddle 6t outwardly to therear, tilting the motor from the position shown in FIGURE 4 to theposition shown in FIGURE 5. The movement of the cylinders continuesoutwardly until the rear edge of the piston reaches port 116. Since thecylinders at this port have reached their maximum travel, the operatorreleases lever 158 shutting oif the supply of compressed gas tocylinders 56 and 58 and permitting them to retract to the point whereplunger 186 seats in recess 188 against shoulder 199 holding thecylinders in their extended position and the motor in the position shownin FIGURE 5. When it is desired to release the motor and lower it to itsrunning position, the operator first presses lever 158 again to admitgas into the cylinders and move the cylinders to the point at which lug203 will force plunger 186 upwardly against member 202 and rotate theplunger sutficiently for pin 198 to seat in the shallow slots 196. Thecylinders are now free to return to their inoperative position shown inFIGURE 4. The rate at which the motor is lowered is regulated bycontrolling exhaust valve 164.

From the foregoing description of the operation it is seen that theentire lifting, locking, unlocking and lowering operations can be fullyperformed by the manipulation of lever 158 and button 174, i.e. byopening and closing easily operated valves 148 and 164, without any needfor the boat operator to leave his seat or to apply any appreciablepressure or use any appreciable physical movement. The simplicity andease of operation of the control unit add greatly to the safety of theoperator and other occupants of the boat in that it is not necessary forthe operator to move around in the boat in order to operate the presentmechanism either to raise or lower the motor. This important feature isin part made possible by the use of the compressed gas cylinder as thesource of power since the operating pressure is provided withoutemploying any moving parts and without the use of any complicated,dilficult to handle control levers or mechanisms. Further, the cylinderof compressed gas is not affected by water or changes in atmosphericcondition and can be placed in normally unused space in the boat withoutdanger of fire or explosion.

Since some outboard motors rotate on their vertical axis 360 degrees forreversing the direction of the boat, the motors include a mechanism forlocking them in their running position, as explained previously herein.While these motors are usually operated with this mechanism in itsunlocked position and hence are in condition to be tilted using themechanism previously described, it may be desirable in some instances toinclude a penumatic means operated by the same control unit 52 tounlatch the locking means the instant pressure is admitted intocylinders 56 and 58. A mechanical means independent of the present motortilting mechanism may be used instead. While cylinders 56 and 58 arepreferably mounted on saddle 60 and rods 80 and 86 attached to thetransom, this arrangement may be reversed if desired. Various otheradditions, modifications and changes may be made in the presentmechanism without departing from the scope of the invention.

I claim:

1. A mechanism for raising and lowering an outboard motor having aframe, a leg depending from said frame for supporting a propeller, andmeans for mounting said motor on the transom of a boat including a pivotforming a horizontal axis on which the motor tilts between operating andnonoperating positions, said mechanism comprising a U-shaped saddle thecross member of which extends horizontally between the transom and theleg of the motor and the arms of which extend rearwardly along oppositesides of the leg, a cylinder secured to each arm and arranged paralleltherewith, a piston in each cylinder, a rod in each cylinder attached tothe piston and extending from the forward end of the cylinder and havinga passage therein communicating with the rearward end of the cylinder,means for pivotally attaching one end of each rod to the boat transom, acylinder of compressed gas, a conduit connecting said gas cylinder withsaid passages in said rods, a valve in said conduit for controlling theflow of gas from said gas cylinder to said first mentioned cylinders, anexhaust valve in said conduit between said control valve and said firstmentioned cylinders, a shut ofi valve in said conduit between saidcompressed gas cylinder and said control valve, a pair of restrictionsin said conduit between said exhaust valve and said first mentionedcylinders, a means for locking one of said piston rods in its extendedposition and the U- shaped saddle in its motor lifted position includinga recess in said one rod, a plunger for seating in said recess, a lugfor retracting said plunger from said recess as said rod is extended,means for alternately placing said plunger in its retracted and extendedpositions for locking and releasing said one rod, and a rod attached toone of said first mentioned cylinders for holding said saddle in itsoperating position.

2. A mechanism for raising and lowering an outboard motor having aframe, a leg depending from said frame for supporting a propeller, andmeans for mounting said motor on the transom of a boat including a pivotforming a horizontal axis on which the motor tilts between operating andnonoperating positions, said mechanism comprising a U-shaped saddle thecross member of which extends horizontally between the transom and theleg of the motor and the arms of which extend rearwardly along oppositesides of the leg, a cylinder secured to each arm and arranged paralleltherewith, a piston in each cylinder, a rod in each cylinder attached tothe piston and extending from the forward end of the cylinder and havinga passage therein communicating with the rearward end of the cylinder,means for pivotally attaching one end of each rod to the boat transom, acylinder of compressed gas, a conduit connecting said gas cylinder withsaid passages in said rods, a valve in said conduit for controlling theflow of gas from said gas cylinder to said first mentioned cylinders, anexhaust valve in said conduit between said control valve and said firstmentioned cylinders, a means for locking one of said first piston rodsin its extended position and the U-shaped saddle in its motor liftedposition including a recess in said one rod, a plunger for seating insaid recess, a lug for retracting said plunger from said recess as saidrod is extended, means for alternately placing said plunger in itsretracted and extended positions for locking and releasing said one rod,and a rod attached to one of said first mentioned cylinders for holdingsaid saddle in its operating position.

3. A mechanism for raising and lowering a boat motor having a frame, aleg depending from said frame for supporting a propeller, and means formounting said motor on the rear of a boat including a pivot forming ahorizontal axis on which the motor tilts between operating andnonoperating positions, said mechanism comprising a saddle having across member extending horizontally between the boat and the leg of themotor and arms extending rearwardly along opposite sides of the leg, acylinder secured to each arm and arranged parallel therewith, a pistonin each cylinder, a rod in each cylinder attached to the piston andextending from the forward end of the cylinder, means for pivotallyattaching one end of each rod to the boat, a cylinder of compressed gas,a conduit connecting said gas cylinder with said first mentionedcylinders, a valve in said conduit for controlling the flow of gas fromsaid gas cylinder to said first mentioned cylinders, a releasable meansincluding an element operated in response to the movement of one of saidpiston rods for locking said one piston rod in and releasing it from itsextended position, and a rod attached to one of said first mentionedcylinders for holding said saddle in its operating position.

4. A mechanism for raising and lowering a boat motor having a frame, aleg depending from said frame for supporting a propeller, and means formounting said motor on the rear of a boat including a pivot forming ahorizontal axis on which the leg tilts between operating andnonoperating positions, comprising a frame having a cross memberextending horizontally between the boat and the leg of the motor andarms extending rearwardly along the opposite sides of the leg, acylinder secured to each arm and arranged parallel therewith, a pistonin each cylinder, a rod in each cylinder attached to the piston andextending from the forward end of the cylinder, means for pivotallyattaching one end of each rod to the boat, a releasable means includingan element operated in response to the movement of one of said pistonrods for locking said one piston rod in and releasing it from itsextended position, a cylinder of compressed gas, a conduit connectingsaid gas cylinder with said first mentioned cylinders, a valve in saidconduit for controlling the fiow of gas from said gas cylinder to saidfirst mentioned cylinders, and an exhaust valve in said conduit betweensaid control valve and said first mentioned cylinders.

5. A mechanism for raising and lowering a boat motor having a frame, aleg depending from said frame for supporting a propeller, and means formounting said motor on the rear of a boat including a pivot forming ahorizontal axis on which the leg tilts between operating andnonoperating positions, comprising a U-shaped frame having a crossmember extending horizontally and arms extending rearward-1y alongopposite sides of the leg, cylinder, piston and rod assemblies havingone end attached to said U-shaped frame on opposite sides thereof andthe other end connected to the boat, a source of compressed gas, aconduit connecting said source with said cylinders, a valve in saidconduit for controlling the flow of gas from said source to saidcylinders, an exhaust valve in said conduit between said control valveand said cylinders, a releasable means including an element operated inresponse to the movement of one of said piston rods for locking said onepiston rod in its extended position and the U-shaped frame in its motorlifted position and for releasing said rod and frame from said position,and a rod connected to said U-shaped frame for holding said frame in itsoperating position.

6. A mechanism for raising and lowering a boat motor having a frame, aleg depending from said frame for supporting a propeller, and means formounting said motor on the rear of a boat including a pivot forming ahorizontal axis on which the leg tilts between operating andnonoperating positions, comprising a frame having a cross memberextending horizontally between the boat and the leg of the motor,cylinder, piston and rod assemblies having one end attached to saidsecond mentioned frame on opposite sides thereof and the other endconnected to the boat, a releasable means including an element operatedin response to the movement of one of said piston rods for locking saidone piston rod in and releasing it from its extended position, a sourceof compressed gas, a conduit connecting said source with said cylinders,a valve in said conduit for controlling the flow of gas from said sourceto said cylinders, and an exhaust valve in said conduit between saidcontrol valve and said cylinders.

7. A mechanism for raising and lowering a boat motor having a'frame, aleg depending from said frame for supporting a propeller, and means formounting said motor on the rear of a boat including a pivot forming ahorizontal axis on which the leg tilts between operating andnonoperating positions, comprising a U-shaped rrame having a crossmember extending horizontally between the boat and the leg of the motorand arms extending rearwardly along opposite sides of the leg, acylinder, piston and rod assembly having one end attached to saidU-shaped frame and the other end arranged to be connected to the boat, asource of compressed gas, a conduit connecting said source with saidcylinder, and a valve in said conduit remotely positioned with respectto said cylinder and having a means for controlling the flow of gas fromsaid source to said cylinder.

8. A mechanism for raising and lowering a boat motor having a leg andmeans for pivoting said leg between operating and nonoperatingpositions, comprising a frame for engaging said leg, a cylinder, pistonand rod assembly having one end attached to said frame and the other endarranged to be connected to the boat, a cylinder of compressed gas, aconduit connecting said gas cylinder with said first mentioned cylinder,and a valve in said conduit for controlling the flow of gas from saidgas cylinder to said first mentioned cylinder, an exhaust valve in saidconduit between said control valve and said first mentioned cylinder,and a releasable means including an element operated in response to themovement of said piston rod for locking said piston rod in its extendedposition and for releasing said rod from said position.

9. A mechanism for raising and lowering a boat motor having a leg andmeans for pivoting said leg between operating and nonoperatingpositions, comprising a frame for engaging said leg, a cylinder, pistonand rod assembly having one end attached to said frame and the other endarranged to be connected to the boat, a cylinder of compressed gas, aconduit connecting said gas cylinder with said first mentioned cylinder,and a valve in said conduit remotely positioned with respect to saidfirst mentioned cylinder and having a means for controlling the flow ofgas from said gas cylinder to and from said first mentioned cylinder.

10. A mechanism for raising and lowering a boat motor having a leg andmeans for pivoting said leg between operating and nonoperatingpositions, comprising a frame for engaging said leg, a cylinder, pistonand rod assembly having one end attached to said frame and the other endarranged to be connected to the boat, a source of compressed gas, aconduit connecting said source with said cylinder, and a valve in saidconduit remotely positioned with respect to said cylinder and having ameans for controlling the flow of gas from said source to and from saidcylinder.

11. In a mechanism for raising and lowering a boat motor having a legand means for pivoting said leg between operating and nonoperatingpositions: a frame for engaging said leg, a cylinder, piston and rodassembly having one end attached to said frame and the other endarranged to be connected to the boat, a means for locking said pistonrod in its extended position including a recess in said rod, a plungerfor seating in said recess, a lug for retracting said plunger from saidrecess as said rod is extended, and means for alternately placing saidplunger in its retracted and extended positions for locking andreleasing said rod.

References Cited in the file of this patent UNITED STATES PATENTS1,286,051 Meyers Nov. 26, 1918 2,562,493 Harris July 31, 1951 2,966,876MacWilliam Jan. 3, 1961 FOREIGN PATENTS 948,854 Germany Sept. 6, 1956

